I can definitely try that. I went back just now and got as close to it as I could and reinspected it’s foot, it looks like it and all the other ducks like it naturally have dark grey spots on their feet, and it’s “problem area” seems to be a swollen part with a dark black spot on top. Attaching a few more photos, one is of it’s sibling, just so you can see the normal version of its coloring. I will round up some animal loving assistance and a net so I can catch this little homie and take it to the bird refuge where it can get some medical care.